I've been writing a custom engine for web using WebAssembly. It has some cool stuff like procedural audio that's shown off a tiny bit in this demo.

To make that audio work I need SharedArrayBuffers, and SharedArrayBuffers require CORS flags to be set as detailed here: https://developer.chrome.com/blog/enabling-shared-array-buffer/

Right now my engine works on itch.io in Chrome without the CORS headers set, but that's temporary and Chrome will be disabling support next month. It's likely very difficult to make my engine work without SharedArrayBuffers, but I'd really like to host my future work on itch.io.

I noticed there was some discussion of this issue around half a year ago: https://itch.io/t/1028526/cross-origin-policies-for-webassembly

Has any further progress been made on this front?

Godot released support for multi-threading today (version 3.3), which requires SharedArrayBuffers. In order to use it in Firefox I’d need the Cross-Origin-Embedder-Policy and Cross-Origin-Opener-Policy headers to be set. Without it, I fall back to loading the game on the main thread which causes everything to freeze (ruins immersion).

Don’t see these headers currently, would really like them!

I also want to register my interest in having these headers added. Mainly for the Godot multi-threading support. I appreciate that it's not as simple as just adding the headers as it may break older game, but if a solution could be found that'd be very nice. :)

Some additional info: I noticed there's now a concrete date when Chrome will require cross-origin isolation to use SharedArrayBuffers: July 20th.

Chrome 92 is making these changes and it will start rolling-out July 20th: https://blog.chromium.org/2021/06/chrome-92-web-apps-as-file-handlers-new.html

Just chiming in that I’m also seeing this error on my game: https://opyate.itch.io/pop1

These headers work for me locally:

“Cross-Origin-Opener-Policy”: “same-origin”

“Cross-Origin-Embedder-Policy”: “require-corp”

Newgrounds supports these headers: https://www.newgrounds.com/bbs/topic/1468978

Thanks for spending time on this!

Same issue with another Godot 3.3 game: https://dexterminator.itch.io/solemates

Need these header too +1